A taxonomic note of Pterocephalus (Caprifoliaceae) from N Iran

Pterocephalus ramianensis (Caprifoliaceae) is described and illustrated as a new species from Golestan Province, north Iran. This species is morphologically and micromorphologically well-differentiated from P. plumosus. The characters that distinguish this new species from P. plumosus are provided along with a key to the Iranian annual species in Pterocephalus.